Locked within ice-like cages that are buried in the sediments below thick Arctic permafrost and beneath the ocean floor, is an immense source of energy that scientists have studied for more than two decades.

Methane hydrates -- gas molecules trapped within a lattice of ice -- could contain more energy than all other known fossil fuels combined. That is, if folks figure out how to produce volumes of methane from hydrate beyond a few small-scale field experiments.

Until then, the testing will continue. ConocoPhillips, the Energy Department and Japan Oil, Gas and Metals National Corp. are conducting the latest round of field experiments, which will focus on a production method that could create an innovative way of storing carbon dioxide.

During the initial field trial set to begin in January 2012, carbon dioxide will be injected into the methane hydrate-bearing sandstone formations, which can be located more than 1,500 feet beneath the ocean floor. Carbon dioxide molecules will be swapped for methane molecules, and aims to achieve two goals: release the methane gas and permanently store the carbon dioxide in the formation. This field experiment will be an extension of earlier successful tests of the technology conducted by ConocoPhillips and its partners in a laboratory setting, the DOE said.

The tests will use the "Iġnik Sikumi" (Iñupiaq for "fire in the ice") gas hydrate field trial well that was installed in Alaska's Prudhoe Bay region by ConocoPhillips and the Office of Fossil Energy’s National Energy Technology Laboratory earlier this year. The team will spend another month evaluating an alternative method of methane production called depressurization, which was successfully demonstrated during a one-week test in a different location by Japan and Canada back in 2008.

Kirsten Korosec has written for Technology Review, Marketing News, The Hill, BNET and Bloomberg News. She holds a degree from Northwestern University's Medill School of Journalism. She is based in Tucson, Arizona.
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